Lewis & Short

2. stagno, āvi, ātum, 1, v. a. [stagnum = stannum; cf. stagneus, s. v. stanneus].

  1. I. Lit., to overlay or plate with stannum (post-class.), Plin. Val. 1, 31 med.; 3, 4 med.
  2. II. Trop., to make fast, strengthen, fortify: se adversus insidias, Just. 37, 2, 6: potionibus stagnata animalia, strengthened, invigorated, Veg. 1, 18 fin.; 3, 2, 5.